1e. Longacres Drive Stormwater Pond Outlet improvement & Lyman Blvd Sewer Repairs: Award of Contract
CITY OF
CHANHASSEN
7700 Markel Boulevard
PO Box 147
Chanhassen, MN 55317
Administralion
Phone: 952.227.1100
Fax: 952.227.1110
Building Inspections
Phone: 952.227.1180
Fax: 952.227.1190
Engineering .
Phone: 952.227.1160
Fax: 952.227.1170
Finance
Phone: 952.227.1140
Fax: 952.227.1110
Park & Recreation
Phone: 952.227.1120
Fax: 952.227.1110
Recreation Center
2310 Coulter Boulevard
Phone: 952.227.1400
Fax: 952.227.1404
Planning &
Natural Resources
Phone: 952.227.1130
Fax: 952.227.1110
Public Works
1591 Park Road
Phone: 952.227.1300
Fax: 952.227.1310
Senior Center
Phone: 952.227.1125
Fax: 952.227.1110
Web Site
WNW.ci .chanhassen.mn.us
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MEMORANDUM
TO:
Todd Gerhardt, City Manager
Paul Oehme,.!'.E., Director of Public Works/City Engineer~ 0,
September 25, 2006 ~
FROM:
DATE:
SUBJ:
Longacres Drive Stormwater Pond Outlet Improvement & Lyman
Boulevard Sewer Repairs: Award of Contract
Project Nos. 06-08 and 06-09
REQUESTED ACTION
Award contract to GL Contracting, Inc.
BACKGROUND
On June 24,
referenced pr
. s on the above
r this projeCt and authoriz.ed
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This bid contains two'; 'cf . ;~~hstruGtion of an emergency
outlet pipe to the Longacres p. comerbf Longacres Drive and
Moccasin Trail. Th~ other is to fixas~ttled seVi':er main under Lyman Boulevard near
the Springfield nei' . "' ^ ....., , , <,}?' ,,;; ,.: ' ~;~I!i;
On September 4 and 5, 2005,Chanhassertex.perienced nearly a 100-year rainfall
event. The stormwater event caused clrainage and erosion problems in many parts of
the city. Newly gradeddeveloPlllent$",ereparticularlysusceptible to erosion and
drainage problems. In the caseofJ-IighcrestMeadows, north of Longacres Dri ve, the
final grading wasnotcolllplet.e,t.hx~sit.e\M~si1otstabilized to withstand the extreme
rainfall and the stormwater infrastructure had not been installed. The volume of
runoff and accompanying debris and sed.iIl1ent caused damage to a nufuber of existing
homes. It also alerted the City to an e.x:istingcondition in the Longacres
neighb?rhood that intensified the. effects of the rain event.
If the Highcrest Meadows deve19Pfl'lent infrastructure would have been completed
and the storm sewer system funct.lQniIlg,impacts to the existing property owners most
likely would not have taken place. However, due to the amount of runoff and debris
that entered the City's storm sewer system from the development, the storm sewer
The City of Chanhassen · A growing community with clean lakes, Quality schools, a charming downtown, thriving businesses, winding trails, and beautiful parks. A greal place to live, work, and play.
I
'.
,
Todd Gerhardt
September 25,20'0'6
Page 2
system became clogged and backed up. Normally, when storm sewer systems backup
or become clogged, an emergency overflow (EOF) system should take the runoff and
channel it over land away fWm structures to minimize the amount of property
damage. At this particular location, an EOP was designed to flow over Longacres
Drive but the road was built approximately 1.5' higher than planned and therefore
restricted the overflow from the pond. Also, the properties on the south side of
Longacres Drive where the EOF was designed to flow between two properties was
not graded to building plan and also restricted the overflow water from the pond.
The scope of the Longacres pond project includes directionally drilling an 18"
emergency outlet pipe from the Longacres pond to the north branch of Bluff Creek.
The 18" emergency outlet pipe is designed to handle runoff from a storm larger then a
1000-year event and provide the pond with another outlet if the primary outlet
becomes clogged again. Directionally drilling the pipe is proposed to minimize the
disruption to the properties along the pipe alignment and decrease the impacts to the
adjacent properties. Additional catch basins along Longacres Drive are also
recommended. Replacement of the outlet structure will provide additional safeguards
from debris clogging the existing structure.
Lyman Boulevard Sanitary Sewer Improvement
On December 16, 20'0'5, a sewer backup occurred in the Summerfield development.
The sewer backup was immediately cleared and the sewer pipe was cleaned by City
staff. In researching why the sewer backed up, it was determined that a segment of
sewer pipe under Lyman Boulevard has settled and caused the sewage to backup.
The area of settlement is adjacent to a wetland complex and it is speculated that poor
soils under the pipe have settled. The sanitary sewer pipe can no longer be
maintained or be relied on for proper sewer flow. It is recommended that the sewer
pipe be replaced and any poor soils under the sewer pipe be removed and replaced
with the necessary pipe bedding material.
DISCUSSION
The bids were received for the above-referenced project on Thursday,
September 14, 20'0'6 at 1:30' p.m. The bids were tabulated and checked for errors.
There were a total of four bids received as follows:
# Contractor Base Bid Alternate No.1 Alternate No.2
1 GL Contracting, Inc. $211,785.70' $14,486.0'0' -$7,0'0'0'.0'0'
2 AB Environmental Corp. $221,782.60' $20',750'.0'0 $0'.0'0'
3 Jay Brothers, Inc. $225,0'24.49 $12,970'.0'0' -$2,000'.0'0'
4 Kusske Construction Co. $230',689.0'0' $15,30'0'.0'0' -$2,0'0'0'.0'0'
G:\ENG\PUBLIOO6-09 Longacres Stonnwnter Pond hnp\bkgd 092506 award contract. doc
Todd Gerhardt
September 25,2006
Page 3
Two alternates were included in the bid. The first alternate was for construction of a
swale between two properties south of the Longacres Drive Stormwater pond. This
swale would be constructed at the low point of the road to create an overflow on the
properties. Since this swale would not help much in terms of overland emergency
flow since the Longacres Drive is still too high to make the swale effective, staff is
recommending rejecting this alternate. The second alternate was for extending the
completion date of the directional drilled pipe. The base bid completion date for this
work is November 15,2006. Staff discussed this alternate with the contractor. The
contractor would like to start the directional boring work at the end of November
2006. Substantial completion of the work would occur at the end of the year. Staff is
recommending this alternate be accepted since it is a substantial cost savings and it
only extends the completion date until the end of the year. The likelihood of a
significant rainfall event late in the fall that could create flooding problems is very
low. Staff will continue to monitor the pond on a more frequent basis until the pipe is
installed. The contract award amount, if Alternate No.2 is accepted, would be
$204,785.70.
The revised engineer's estimate was $190,000. The bid is $14,758.70 higher then the
engineers estimate. The difference is mainly in the cost of the directional bored pipe
for the Longacres Drive project and the cost of bituminous mix for the Lyman
Boulevard project. The cost of the directionally drilled pipe has been rising over the
last year and it is very difficult to predict the cost of the pipe. Also, a limited amount
of contractors are available to directional bore. The cost of bituminous pavement
keeps increasing. Bituminous material costs have risen substantially over the past
year. Staff does not believe rebidding the project will generate better bids.
The cost for the Longacres Drive construction project is $146,854.60 if Alternate No.
2 is accepted. These improvements were not budgeted for in the 2006 CIP since no
project was envisioned at that time. However, in this year's 2006 Street Improvement
Project, $136,251.70 out of the $400,000 budgeted (SWMP-019) was used. Staff is
proposing to use this CIP item for constructing of the Longacres Pond improvements.
The Lyman Boulevard construction cost improvements are $57,931.10. The Lyman
Boulevard sanitary sewer improvements were not budgeted for in the 2006 CIP since
no project was envisioned at that time. However, in this year's 2006 Street
Improvement Project, only $55,426.25 out of the $310,000 budgeted (SS-014) was
used. Staff is proposing this CIP item for the Lyman Boulevard sanitary sewer
improvements.
RECOMMENDA TION
Staff is recommending awarding this project to GL Contracting, Inc. in the amount of
$204,785.70.
c: Mark Statz, Bonestroo & Associates
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